In an existing software system which searches a literature set with a keyword specified by a user to acquires a bio-item (hereinafter, a gene will be taken as an example) related to the keyword from the searching result, a method of calculating correlation scores between literatures and the keyword, ranking the literatures, and then displaying gene-related terms described in the literatures is used.
As a method for finding a promising gene closely related to the keyword, Patent Document 1 discloses a method for estimating a gene correlation from timings of expression of the genes. Patent Document 2 discloses an apparatus that performs link-searching for searching for objects connecting end-point keys, prioritizes the genes, takes in and searches for promising genes in a plurality of genes, and shows the promising genes with priorities.
Patent Documents 3 to 5 disclose methods for grouping keywords and searching for related keywords to make it easy to select keywords. More specifically, Patent Document 3 discloses an apparatus that searches with a keyword and keywords related to the keyword simultaneously and groups related keywords. Patent Document 4 discloses grouping of keyword. Patent Document 5 discloses an apparatus that extracts proven design data from a plurality of pieces of design data and evaluates design data by a statistic process.
A Generic Engine for Transposable Association (GETA) described in Nonpatent Literature 1 (accomplishment report in 2001) discloses a tool that rapidly calculates a similarity between rows or between columns (more specifically, between documents or between words) by an inner product measure in a large-scale and rough matrix typified by frequency index data (data representing a frequency of appearance of a specific word in a specific document) in a document search.    Patent Document 1: JP-A-2003-141123    Patent Document 2: JP-A-2001-290822    Patent Document 3: JP-A-8-30629    Patent Document 4: JP-A-2006-72671    Patent Document 5: JP-A-10-149376    Nonpatent Literature 1: Akihiko TAKANO et al., “Development of the generic association engine for processing large corpora”, [online], 2002, Akihiko TAKANO, [searched on 23 Mar. 2007], the Internet <URL:http://geta.ex.nii.ac.jp/pdf/itx2002.pdf>